You obtain 6 BACs (of known order, as shown below) and 7 STSs (of unknown order) that derive from a region of mouse chromosome 16 whose genomic sequence has not yet been finished.   

 

By PCR (using 20-bp primers at either end of each STS), you test each of the 6 BACs for the presence (+) or absence (-) of each of the 7 STSs. You obtain the following results:

 

Is there a second STS at which you would like to sequence PCR products obtained using BACs as templates? If so, which BACs would you test in this way, and what sequencing results might you predict for each of the BACs tested?

TLS Online TPP Program

#Question id: 16142

#Unit 4. Cell Communication and Cell Signaling

Stem cells are defined by two capacities:

(1) the ability to regenerate or “self-renew” and

(2) the ability to differentiate into all diverse cell types. Embryonic stem cells have the capacity to generate every specialized cell type in an organism, in other words,

TLS Online TPP Program

#Question id: 16143

#Unit 4. Cell Communication and Cell Signaling

undifferentiated hematopoietic stem cells would not express surface markers specific for mature cells from the multiple blood lineages (“Lin” markers). They used several approaches to eliminate cells in the bone marrow that did express these markers (Lin+ cells) and then examined the remaining (Lin+) population for its potential to continually give rise to all blood cells over the long term. Lin- cells were, indeed, enriched for this potential. what marker is   express If cells inter in lymphoid lineages?

TLS Online TPP Program

#Question id: 16144

#Unit 4. Cell Communication and Cell Signaling

  _______are motile phagocytic cells they play their most important role in the defense against multicellular parasitic organisms, including worms. They can be found clustering around invading worms, whose membranes are damaged by the activity of proteins released from its granules. it may also secrete cytokines that regulate B and T lymphocytes, thereby influencing the adaptive immune response.

TLS Online TPP Program

#Question id: 16145

#Unit 4. Cell Communication and Cell Signaling

 Which line is not true for follicular dendritic cells?

TLS Online TPP Program

#Question id: 16146

#Unit 4. Cell Communication and Cell Signaling

If a given lymphocyte divides to form two daughter cells, both daughters bear antigen receptors with antigen specificities identical to each other and to the parental cell from which they arose, and so will any descendants they produce. The resulting population of lymphocytes, all arising from the same founding lymphocyte, is a clone. Which interleukin is responsible for clone production?

TLS Online TPP Program

#Question id: 16147

#Unit 4. Cell Communication and Cell Signaling

 Which statement is not true for Natural killer (NK) cells?